[S390] hibernation: fix register corruption on machine checks (c63b196a) · Commits · 戴 / test

arch/s390/power/swsusp.c

+24 −12

Original line number	Diff line number	Diff line
		@@ -7,24 +7,36 @@
		*
		*/

		#include <asm/system.h>

		/*
		* save CPU registers before creating a hibernation image and before
		* restoring the memory state from it
		*/
		void save_processor_state(void)
		{
		/* implentation contained in the
		* swsusp_arch_suspend function
		/* swsusp_arch_suspend() actually saves all cpu register contents.
		* Machine checks must be disabled since swsusp_arch_suspend() stores
		* register contents to their lowcore save areas. That's the same
		* place where register contents on machine checks would be saved.
		* To avoid register corruption disable machine checks.
		* We must also disable machine checks in the new psw mask for
		* program checks, since swsusp_arch_suspend() may generate program
		* checks. Disabling machine checks for all other new psw masks is
		* just paranoia.
		*/
		local_mcck_disable();
		/* Disable lowcore protection */
		__ctl_clear_bit(0,28);
		S390_lowcore.external_new_psw.mask &= ~PSW_MASK_MCHECK;
		S390_lowcore.svc_new_psw.mask &= ~PSW_MASK_MCHECK;
		S390_lowcore.io_new_psw.mask &= ~PSW_MASK_MCHECK;
		S390_lowcore.program_new_psw.mask &= ~PSW_MASK_MCHECK;
		}

		/*
		* restore the contents of CPU registers
		*/
		void restore_processor_state(void)
		{
		/* implentation contained in the
		* swsusp_arch_resume function
		*/
		S390_lowcore.external_new_psw.mask \|= PSW_MASK_MCHECK;
		S390_lowcore.svc_new_psw.mask \|= PSW_MASK_MCHECK;
		S390_lowcore.io_new_psw.mask \|= PSW_MASK_MCHECK;
		S390_lowcore.program_new_psw.mask \|= PSW_MASK_MCHECK;
		/* Enable lowcore protection */
		__ctl_set_bit(0,28);
		local_mcck_enable();
		}

arch/s390/power/swsusp_asm64.S

+1 −21

Original line number	Diff line number	Diff line
		@@ -32,11 +32,6 @@ swsusp_arch_suspend:
		/* Deactivate DAT */
		stnsm __SF_EMPTY(%r15),0xfb

		/* Switch off lowcore protection */
		stctg %c0,%c0,__SF_EMPTY(%r15)
		ni __SF_EMPTY+4(%r15),0xef
		lctlg %c0,%c0,__SF_EMPTY(%r15)

		/* Store prefix register on stack */
		stpx __SF_EMPTY(%r15)

		@@ -88,11 +83,6 @@ swsusp_arch_suspend:
		/* Save image */
		brasl %r14,swsusp_save

		/* Switch on lowcore protection */
		stctg %c0,%c0,__SF_EMPTY(%r15)
		oi __SF_EMPTY+4(%r15),0x10
		lctlg %c0,%c0,__SF_EMPTY(%r15)

		/* Restore prefix register and return */
		lghi %r1,0x1000
		spx 0x318(%r1)
		@@ -120,11 +110,6 @@ swsusp_arch_resume:
		/* Deactivate DAT */
		stnsm __SF_EMPTY(%r15),0xfb

		/* Switch off lowcore protection */
		stctg %c0,%c0,__SF_EMPTY(%r15)
		ni __SF_EMPTY+4(%r15),0xef
		lctlg %c0,%c0,__SF_EMPTY(%r15)

		/* Set prefix page to zero */
		xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
		spx __SF_EMPTY(%r15)
		@@ -178,7 +163,7 @@ swsusp_arch_resume:
		/* Load old stack */
		lg %r15,0x2f8(%r13)

		/* Pointer to save arae */
		/* Pointer to save area */
		lghi %r13,0x1000

		#ifdef CONFIG_SMP
		@@ -190,11 +175,6 @@ swsusp_arch_resume:
		/* Restore prefix register */
		spx 0x318(%r13)

		/* Switch on lowcore protection */
		stctg %c0,%c0,__SF_EMPTY(%r15)
		oi __SF_EMPTY+4(%r15),0x10
		lctlg %c0,%c0,__SF_EMPTY(%r15)

		/* Activate DAT */
		stosm __SF_EMPTY(%r15),0x04

Admin message